<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>flex(项目属性)布局实战</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        #box {
            display: flex;
            flex-direction: row;
            background-color: #333333;
            width: 600px;
        }

        #box .child {
            flex: 1;
            background-color: aquamarine;
            margin: 5px;
        }
    </style>
</head>

<body>
    <div id="box">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
    </div>
</body>